SACRAMENTO — A former California state parks employee says she told state attorneys her department was hiding about $20 million in a special fund several months before officials announced discovering the surplus money, according to a sworn declaration filed in court Tuesday.

The development is the latest revelation in a budget scandal that has state officials on the defensive and threatens to undermine Gov. Jerry Brown’s push for a voter-approved tax increase.

The court declaration from Cheryl Taylor, a former parks employee, raises further questions about what state officials knew, when they knew it, and what action, if any, they took before the California Natural Resources Agency revealed the hidden pot of money in July.

Such special funds contribute to the state’s general fund budget each year as lawmakers take millions of dollars in loans from the funds to close budget deficits.

To plug this year’s budget gap, the governor proposed closing 70 state parks to save $33 million over two years, prompting a scramble by local governments and nonprofits to raise money and keep most of the parks open this summer. Brown also has pushed a message of fiscal responsibility as he has urged voters to increase the state’s revenue by approving a tax hike in November.

The administration said it publicly disclosed the accounting problem within 48 hours of the discovery in July.

But, according to Taylor’s statement, officials should have known much sooner, said Elisa Stewart, a San Francisco attorney who filed the declaration.

Taylor, according to her statement, first told a representative of the state attorney general’s office in January about the hidden $20 million and that the budget manager for the parks department had warned employees to keep the underreporting quiet.

Taylor’s declaration is part of a sexual harassment lawsuit naming Manuel Lopez, the state parks’ former budget manager who is at the center of multiple investigations. State attorneys were tracing an unauthorized vacation buyout program organized by Lopez when they questioned Taylor about department finances.

Her sworn declaration, filed in Sacramento County Superior Court, says she told Deputy Attorney General Corrine Lee Murphy and parks department staff attorney Jennifer Comilang in April that she “was aware of the underreporting of funds,” but that Lopez had told her not to report the information. She also told the attorneys that Lopez had ordered her to demote an employee who reported the $20 million surplus in the spring of 2010.

Taylor said in her declaration that she had a similar conversation by telephone in January with the state Department of Justice, which is run by the attorney general’s office. She recalled explaining the department’s budget “in great detail” as she discussed whether Lopez would have access to department funds without going through the Legislature.

She did not name the individual, but remembered the conversation as being within days of Gov. Jerry Brown proposing his budget on Jan. 5. The attorney general’s office assigned Murphy to the investigation Jan. 9, according to her official report.

It’s unclear if the state attorneys relayed Taylor’s information to anyone else.

The attorney general’s office and state parks department declined comment, citing the ongoing investigation into the underreported money.